A Case Study in NASA-DoD - The Black Vault

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decrease any total program cost advantage that the option might have.
To illustrate this, three to four additional MMS in the upgraded AEM/MMS
option would eliminate the difference in program cost between the pure
L-AEM option and the upgraded AEM/MHS option for the nominal case.
In addition, one of the current Air Force requirements of new
spacetraft is to minimize single-point failure modes in the spacecraft
design. As indicated in Appendix I, that was one of the specifications
for the L-AEM design and has been accounted for in its recurring cost.
To illustrate the effect on program cost of increasing AEM redundancy
so that the L-AEM and the upgraded AEM options will be more comparable,
an excursion was made in which it was assumed that whenever an AEM or
upgraded AEM is included in an option, two spacecraft would be flown
in the same shuttle. The results are shown in Table 15. It can be seen
that for the case of 114 payloads and 6 payloads per spacecraft, several
L-AEM options are within the lower 10 percent cost category; for a mission
model with 228 payloads, the L-AEM options are clearly preferred
over the upgraded AEM/MMS option.
Considering that the program cost advantage indicated for the upgraded
AEM/MMS option over the L-AEM option could be lost in either of
the two ways mentioned above, i.e., by growth in the power and/or weight
requirements of the Air Force Space Test Program mission model, or by
spacecraft design requirement for minimizing single-point failure modes,
it is conctuded that the L-AEM spacecraft, or some very simiZar design,
would provide a basis for minimizing the Air Force Space Test Progran
costs. The L-AEM could be used individually or in combination with the
AEM and/or the MMS. This conclusion is reinforced by the analysis of
a variety of procurement options that considered the uncertainties in
the spacecraft costs and designs, the Air Force Space Test Program
mission model, and the shuttle cost and tariff schedule.
The procurement results for the nominal case that include the
L-AEM are shown in Table 16.
A comparison of these options indicates
This idea was suggested by Boeing as a way of achieving the desired
level of redundancy without redesigning the entire spacecraft.
Physically it is possible to have two AEM spacecraft side by side
within the envelope of the L-AEM.